A lifespan is how long something typically lasts from start to finish.

A lifespanlifespan，is how long something typically lasts from start to finish是指某樣東西從頭到尾通常能維持多久。

For a person or animal, it is the usual number of years they live. For a machine, a battery, a building, or even a company, it is how long it keeps working before it wears out or dies.

For a person or animal對人或動物來說，it is the usual number of years they live它是指他們通常能活的年數。For a machine, a battery, a building, or even a company對機器、電池、建築物，甚至一家公司來說，it is how long it keeps working before it wears out or dies它是指東西在耗損或壽終之前還能運作多久。

Doctors and scientists like it with numbers (the average lifespan of a cat). Product people use it the same way for phones and light bulbs.

Doctors and scientists like it with numbers醫生和科學家喜歡搭配數字使用（the average lifespan of a cat像the average lifespan of a cat，一隻貓的平均壽命）。Product people use it the same way產品業的人也用同樣的方式使用它，for phones and light bulbs用在手機和燈泡上。

It is a calm, slightly textbook word; in chat you might just say how long they live. It looks at the whole stretch of time, not one special day, and it can be average (what is typical) or the span of one particular life.

It is a calm, slightly textbook word這是個平穩、有點教科書味的字；in chat you might just say how long they live聊天的時候你可能就直接說牠們能活多久。It looks at the whole stretch of time它看的是整段時間，not one special day而不是某個特別的日子，and it can be average (what is typical)它可以是average（一般平均），or the span of one particular life也可以是指某一個個體生命的長度。